The effect of silver nanoparticles on composite shear bond strength to dentin with different adhesion protocols

Abstract

In Dentistry, restorative materials and oral bacteria are believed to be responsible for restoration failure. To make long-lasting restorations, antibacterial agents should be made. Inorganic nanoparticles and their nano composites are applied as good antibacterial agents. Objective The purpose of this study was to investigate the effect of silver nanoparticles on composite shear bond strength using one etch and rinse and one self-etch adhesive systems.Material and Methods Silver nanoparticles were prepared. Transmission electron microscope and X-ray diffraction were used to characterize the structure of the particles. Nanoparticles were applied on exposed dentin and then different adhesives and composites were applied. All samples were tested by universal testing machine and shear bond strength was assesed.Results Particles with average diameter of about 20 nm and spherical shape were found. Moreover, it was shown that pretreatment by silver nanoparticles enhanced shear bond strength in both etch and rinse, and in self-etch adhesive systems (p≤0.05).Conclusions Considering the positive antibacterial effects of silver nanoparticles, using them is recommended in restorative dentistry. It seems that silver nanoparticles could have positive effects on bond strength of both etch-and-rinse and self-etch adhesive systems. The best results of silver nanoparticles have been achieved with Adper Single Bond and before acid etching.

Effect of Silver Nanoparticles, Zinc Oxide Nanoparticles and Titanium Dioxide Nanoparticles on Microshear Bond Strength to Enamel and Dentin

“…The second mechanism was used in the current study. 11,23,24 The microshear bond test has been used in the current study to evaluate the bond strength of the dental adhesive to the tooth structure. The microshear test is a reliable and facile method which has overcome the drawbacks of the macroshear test, including inhomogeneous distribution of stress in the area over which the load is applied, the occurrence of the failure in the dentinal substrate at much lower stresses than the substrate strength and the mixed loading mode.…”

“…Moreover, no adverse effect was seen after application of 1 wt% SNPs on the color of composite resins. 11 Based on the findings of the mentioned previous study, the selected concentrations for the nanoparticles in the current study were 1 % to prevent the detrimental effect of these NPs on the color of composite resins. As with the previous study, 15 visual observation did not reveal any color change after application of the nanoparticles with 1 wt% concentrations in this study.…”

“…9 Besides adding active antimicrobial ingredients to the dental materials, another strategy for bacterial reduction is coating surfaces with antibacterial agents to create anti-adhesive surfaces. 10,11 Recently, nanomaterials referring to the materials with a size of less than 100 nm have captured more attention from researchers in dentistry because of their unique properties and structures such as small size, large surface area, a large proportion of surface atoms and high surface energy. 12 In this regard, different metal NPs have been used in various dental branches because of their antibacterial properties.…”

“…17 A recently published study indicated that an additional pretreatment with SNPs had positive effects on the bond strength of etch-and-rinse and self-etch adhesives with the best results reported for Adper Single Bond and before acid etching. 11 Similar to SNPs, ZNPs have exhibited antibacterial effects against several types of gram-negative and grampositive bacteria, including S. mutans and Lactobacillus in dental plaque. 18,19 In fact, ZNPs have demonstrated selective toxicity against bacteria with minimal effects on human cells.…”

“…16 Recently, application of metal-based nanoparticles to improve bond strength properties of composite resins has attracted more attention. 11,13 To the authors' knowledge there are no published studies that address the effect of SNPs, ZNPs and TNPs pretreatments on the bond strength of the composite resin to enamel and dentin. The inherent bactericidal property of NPs has prompted us to investigate the role of SNPs, ZNPs and TNPs pretreatments on the microshear bond strength of the composite resin to enamel and dentin in the present study.…”